The present invention generally relates to address indicator control devices in rotary recording medium reproducing apparatuses, and more particularly to an address indicator control device capable of indicating a predetermined address for a predetermined time period, even when search with respect to a preset address is completed within an exceedingly short period of time, in a rotary recording medium reproducing apparatus having an address indicator device for selectively indicating one address among a plurality of addresses.
A new information signal recording and/or reproducing system has been proposed in U.S. Pat. Nos. 4,315,283 and 4,322,836, of which the assignee is the same as that of the present application. According to this proposed system, the recording system forms pits in accordance with an information signal being recorded along a spiral track on a flat rotary recording medium (hereinafter simply referred to as a disc), without forming a groove therein. In the reproducing system, a reproducing stylus traces over along this track to reproduce the recorded information signal in response to variations in electrostatic capacitance.
In this system, since no grooves for guiding the reproducing stylus are provided on the disc, it becomes necessary to record pilot or reference signals on or in the vicinity of a track of a program information signal, on the disc. Upon reproduction, the reference signals are reproduced together with the program information signal. Tracking control is carried out so that the reproducing stylus accurately traces along the track in response to the reproduced reference signals.
By use of this previously proposed system, there is no possibility whatsoever of the reproducing stylus or the disc being damaged, since the recording track has no groove. The reproducing stylus can trace the same portion of the track repeatedly many times, whereby a special reproduction such as still, slow-motion, or quick-motion reproduction becomes possible. Moreover, operations such as a random access, high-speed search, and automatic cueing operation in which the reproducing stylus is shifted to a position of a desired recorded program where the reproduction is to be started, can be performed with ease.
In order to perform operations such as the above random access, high-speed search, and automatic cueing operations, signals such as an address signal (hereinafter referred to as a chapter address signal) for indicating the position of the recorded program number, and an address signal (hereinafter referred to as a time address signal) for indicating the position within the recorded program in reproducing time position from the start of that recorded program or in reproducing time position (hereinafter referred to as a time address) from the start of the first program recorded on the disc, are recorded onto the disc.
If two indicator devices are respectively provided exclusively for indicating the above chapter address and the time address in the disc reproducing apparatus, this will increase the manufacturing cost and be fruitless. Accordingly, a single address indicator device is generally provided to selectively indicate the chapter address and the time address.
In the above address indicator device, the indicator device indicates the time address when the indication mode of the indicator device is a time address indication mode, for example. In this state, when a desired program chapter is to be searched, for example, a chapter address is set. Next, when a search operation is started, the indicator device indicates the set chapter address, and a reproducing transducer is moved at a high speed. When the search by the reproducing transducer with respect to the set chapter address is completed, the indicator device again indicates the time address on the disc where the movement of the reproducing transducer is completed, according to the indication mode which has been preset.
For example, in a case where the reproducing transducer is at a position on the disc where the chapter address is "12" and the time address is "15 minutes and 42 seconds" and the indication mode of the indicator device is a time address indication mode, the indicator device indicates "15 minutes and 42 seconds". Hence, if the program chapter "15" is to be searched, for example, the chapter address "15" is set. Then, the indicator device indicates the set chapter address "15" when the reproducing apparatus is operated to perform the search, and this indication of the set chapter address remains during the period when the reproducing apparatus is performing the serach operation. Upon completion of the search operation, the indicator device indicates the time address at the beginning of the chapter address "15", that is, "19 minutes and 10 seconds", for example, and thereafter continues to indicate the time address.
In the above example, assume that the time address "15" is close to the end of the program chapter "12" and the program chapter "13" is set as the chapter to be searched. In this case, the search will be performed when the reproducing apparatus is operated to perform the search operation, however, the reproducing transducer will reach a position at the beginning of the program chapter "13" within an exceedingly short period of time. Thus, the duration of the search operation will be 0.1 seconds, for example, which is exceedingly short. Here, the indicator device will indicate the program chapter "13" upon starting of the search operation, but the indication in the indicator device will be returned to the time address indication after an exceedingly short time period of 0.1 seconds, for example. Accordingly, the indication of the program chapter which is to be searched is only obtained for an exceedingly short period of time. Hence, there was a disadvantage in that it became difficult for the operator to check with the indicator device which program chapter was actually searched.